I would say the answer to your questions are all., “Yes.” With regard to question one, there will be some very minor fluctuations, but the general statement is true. You should be able to prove that with a timing light.
Question three, yes, as the mag plate moves towards full throttle, the timing advances, usually a good deal beyond top dead center. At lower speeds, it will be retarded, sometimes to the point where it actually fires AFTER top dead center. The actual maximum and minimum degrees of advance and retard depend entirely on the specific motor’s design.
Whether being fired by points or modules, I think you will find that if all other things are okay with the engine, then if you get a timing light flash anywhere between the two index marks, it will be a good runner. We all strive to make it exact; but the engine will be amazingly tolerant as long as it fires between the two marks…or even on either mark. Now what you can do, is run the engine fast, run the engine medium and run the engine slow and see if the flashes come outside the marks at any time. With points and a worn mag plate, you would likely see the flashes move in and out of the marks, as you move from fast to slow and back to fast. The modules should improve this; but if the plate is worn enough, you might still see fluctuation outside the marks. It’s worth the experiment.
Long live American manufacturing!
